1. Field of the Invention
The present invention relates to a miniaturized planar antenna for digital television reception and, more particularly, to a miniaturized planar antenna, which is formed in a rampart-line manner by the use of printed copper foil technology, thereby to shrink the antenna size and effectively receive signals of digital television.
2. Description of Prior Arts
Presently, there are three kinds of standards for the digital television broadcasting, which are ATSC promoted by U.S., DVB-T of EU, and ISDB-T of Japan, and each of whom has its respective advantages.
However, U.S. has encountered a serious problem of multi-path problem when promoting ATSC standard; that is, corresponding signals of ATSC system may not be received via indoor antennas, and they should be replaced by larger-size outdoor antennas for the purpose of interference attenuation. On the other hand, COFDM signals of DVB-T system are proved to be with the stronger ability of dealing with multi-path interference.
Moreover, the DVB-T system has mobile reception capacity. In the future media environment, digital television channels are no longer restricted to transmission of television programs, but can provide services like data broadcasting for the trendy wireless and mobilized development. The DVB-T system also can deal with electromagnetic waves from many directions for further signal enhancement. That is why the DVB-T system can incorporate with the single frequency network (SFN).
Because the characteristic of mobile reception, the DVB-T system can further provide high-fidelity television programs and data transmission services to passengers in buses, trains, taxis, sedans, or recreation vehicles.
However, the digital television antenna of DVB-T system has drawbacks like large size and inferior portability, resulting in the bottleneck while in promotion.
The primary object of the present invention is to provide a miniaturized planar. antenna of digital television, which can be used in the DVB-T system to improve the aforementioned drawbacks of conventional DVB-T antennas. The present invention antenna is miniaturized and planarized to facilitate portability and mobility.
To achieve the above object, the present invention provides a miniaturized planar antenna of digital television. The present invention antenna includes a substrate and a plurality of radiators. Strip lines are set on each of the upper and lower surfaces of the substrate via the printed copper foil technology. The antennas are arranged in a rampart-line manner, and parallel disposed on the upper and lower surfaces of the substrate. The antennas intersect the stripe lines, and are distributed in two symmetric quadrants, each of which includes at least three sets of antennas.
The present invention also provides a miniaturized planar antenna of digital television having a plurality of substrates and antennas. These substrates are grouped into first substrates, second substrates, and insulating substrates, respectively. The insulting substrate is sandwiched by the first and second substrates. Strip lines are set on each of the upper and lower surfaces of the first and second substrates by the printed copper foil technology. The antennas are arranged in a rampart-line manner, and parallel disposed on the upper and lower surfaces of the first and second substrates, and intersect the stripe lines. The antennas are distributed in the second and fourth quadrants on the upper and lower surfaces of the first substrate and in the first and third quadrants on the upper and lower surfaces of the second substrate. Each quadrant includes at least three pairs of antennas.